package com.sky.aspect;

import com.sky.annotation.AutoFill;
import com.sky.constant.AutoFillConstant;
import com.sky.context.BaseContext;
import com.sky.enumeration.OperationType;
import lombok.extern.slf4j.Slf4j;
import org.aspectj.lang.JoinPoint;
import org.aspectj.lang.annotation.Aspect;
import org.aspectj.lang.annotation.Before;
import org.aspectj.lang.annotation.Pointcut;
import org.aspectj.lang.reflect.MethodSignature;
import org.springframework.stereotype.Component;

import java.lang.reflect.Method;
import java.time.LocalDateTime;

/**
 * 自定义切面类
 */
@Aspect
@Component
@Slf4j
public class AutoFillAspect{
    //指定切入点
    @Pointcut("execution(* com.sky.mapper.*.*(..)) && @annotation(com.sky.annotation.AutoFill)")
    public void autoFillPointCut(){}

    //指定通知, 在通知中进行公共字段赋值
    @Before("autoFillPointCut()")
    public void autoFill(JoinPoint joinPoint){
        log.info("开始进行公共字段的自动填充");

        /*Step1. 获取当前被拦截的方法的数据库操作类型*/
        MethodSignature methodSignature = (MethodSignature) joinPoint.getSignature(); //获得方法签名对象
        AutoFill autoFill = methodSignature.getMethod().getAnnotation(AutoFill.class); //获得注解对象
        OperationType operationType = autoFill.value(); //获得数据库操作类型

        /*Step2. 获取操作实体employee 或 其他实体*/
        Object[] args = joinPoint.getArgs(); //如果没有获取到参数直接返回
        if(args == null || args.length ==0){
            return;
        }
        Object entity = args[0];

        /*Step3. 准备数据 createUser createTime updateUser updateTime*/
        LocalDateTime now = LocalDateTime.now();
        Long currentId = BaseContext.getCurrentId();

        /*Step4. 通过反射 根据不同的操作类型为对象进行赋值*/
        if(operationType == OperationType.INSERT){ //INSERT
            //为四个公共字段赋值
            try {
                Method setCreateTime = entity.getClass().getDeclaredMethod(AutoFillConstant.SET_CREATE_TIME, LocalDateTime.class);
                Method setCreateUser = entity.getClass().getDeclaredMethod(AutoFillConstant.SET_CREATE_USER, Long.class);
                Method setUpdateTime = entity.getClass().getDeclaredMethod(AutoFillConstant.SET_UPDATE_TIME, LocalDateTime.class);
                Method setUpdateUser = entity.getClass().getDeclaredMethod(AutoFillConstant.SET_UPDATE_USER, Long.class);

                setCreateTime.invoke(entity, now);
                setCreateUser.invoke(entity, currentId);
                setUpdateTime.invoke(entity, now);
                setUpdateUser.invoke(entity, currentId);
            } catch (Exception e) {
                e.printStackTrace();
            }
        }else if(operationType == OperationType.UPDATE){ //UPDATE
            //为两个公共字段复制
            Method setUpdateTime = null;
            try {
                setUpdateTime = entity.getClass().getDeclaredMethod(AutoFillConstant.SET_UPDATE_TIME, LocalDateTime.class);
                Method setUpdateUser = entity.getClass().getDeclaredMethod(AutoFillConstant.SET_UPDATE_USER, Long.class);

                setUpdateTime.invoke(entity, now);
                setUpdateUser.invoke(entity, currentId);

            } catch (Exception e) {
                throw new RuntimeException(e);
            }
        }
    }
}
